Obsolete old m68k systems.
* configure.host: Mark m68*-sun-*, m68*-sun-sunos4*,
m68*-sun-sunos3*, m68*-motorola-*, m68*-*-sysv4*, m68*-*-lynxos*,
m68*-bull*-sysv*, m68*-att-*, m680[01]0-sun-sunos4*, and
m680[01]0-sun-sunos3* as obsolete.
* configure.tgt: Mark m68*-*-lynxos*, m68*-*-sunos3*,
m68*-*-sunos4*, m68*-*-sysv4*, m68000-*-sunos3*, m68000-*-sunos4*,
m68*-bull-sysv*, m68*-att-*, and m68*-motorola-*, as obsolete.
* config/m68k/sun3os4.mh: Mark file obsolete.
* config/m68k/xm-sun3os4.h: Mark file obsolete.
* config/m68k/sun3os3.mh: Mark file obsolete.
* config/m68k/nm-sun3.h: Mark file obsolete.
* config/m68k/xm-sun3.h: Mark file obsolete.
* config/m68k/sun2os4.mh: Mark file obsolete.
* config/m68k/sun2os3.mh: Mark file obsolete.
* config/m68k/nm-sun2.h: Mark file obsolete.
* config/m68k/xm-sun2.h: Mark file obsolete.
* config/m68k/m68kv4.mh: Mark file obsolete.
* config/m68k/nm-sysv4.h: Mark file obsolete.
* config/m68k/xm-m68kv4.h: Mark file obsolete.
* config/m68k/m68klynx.mh: Mark file obsolete.
* config/m68k/nm-m68klynx.h: Mark file obsolete.
* config/m68k/dpx2.mh: Mark file obsolete.
* config/m68k/xm-dpx2.h: Mark file obsolete.
* config/m68k/nm-dpx2.h: Mark file obsolete.
* config/m68k/delta68.mh: Mark file obsolete.
* config/m68k/xm-delta68.h: Mark file obsolete.
* config/m68k/nm-delta68.h: Mark file obsolete.
* config/m68k/3b1.mh: Mark file obsolete.
* config/m68k/xm-3b1.h: Mark file obsolete.
* config/m68k/sun3os4.mt: Mark file obsolete.
* config/m68k/tm-sun3os4.h: Mark file obsolete.
* config/m68k/sun3os3.mt: Mark file obsolete.
* config/m68k/tm-sun3.h: Mark file obsolete.
* config/m68k/sun2os4.mt: Mark file obsolete.
* config/m68k/tm-sun2os4.h: Mark file obsolete.
* config/m68k/sun2os3.mt: Mark file obsolete.
* config/m68k/tm-sun2.h: Mark file obsolete.
* config/m68k/m68kv4.mt: Mark file obsolete.
* config/m68k/tm-m68kv4.h: Mark file obsolete.
* config/m68k/m68klynx.mt: Mark file obsolete.
* config/m68k/tm-m68klynx.h: Mark file obsolete.
* config/m68k/dpx2.mt: Mark file obsolete.
* config/m68k/tm-dpx2.h: Mark file obsolete.
* config/m68k/delta68.mt: Mark file obsolete.
* config/m68k/tm-delta68.h: Mark file obsolete.
* config/m68k/3b1.mt: Mark file obsolete.
* config/m68k/tm-3b1.h: Mark file obsolete.
* exec.c (ignore): Return 0.
* stack.c (return_command): Fetch lazy value directly, not via
VALUE_CONTENTS, to avoid "value computed is not used".
* inflow.c (new_tty): Move osigttou inside #if.
* remote.c (remote_fetch_registers): If remote reply is short, just
note that fact and keep going (reading extra registers as all bits 0).
(remote_store_registers): Send number of registers that were found
by remote_fetch_registers.
* m68k-tdep.c, config/m68k/tm-m68k.h, config/m68k/tm-*.h: Remove
HAVE_68881. Define CANNOT_STORE_REGISTER if ptrace() can't write
floating registers.
* config/m68k/{tm-m68k-nofp.h,m68k-nofp.mt,tm-m68k-fp.h,m68k-fp.mt}:
Remove, replaced by {tm-m68k-em.h,m68k-em.mt}.
* Makefile.in, configure.in: Change accordingly.
config files moved to an appropriate config/<cpu> subdirectory.
* nm-*, xm-*, tm-*: All native, host, and target files, which
get linked to nm.h, xm.h, and tm.h respectively by configure,
moved to appropriate config/<cpu> subdirectory.